Khan Pearlin Amaan, Raheem Ansheed, Kalirajan Cheirmadurai, Prashanth Konda Gokuldoss, Manivasagam Geetha
Centre for Biomaterials, Cellular, and Molecular Theranostics, Vellore Institute of Technology, Vellore 632014, India.
Tallinn University of Technology, Ehitajate tee 5, 19086 Tallinn, Estonia.
ACS Mater Au. 2024 Jun 13;4(5):479-488. doi: 10.1021/acsmaterialsau.4c00016. eCollection 2024 Sep 11.
Biomimetic approaches to implant construction are a rising frontier in implantology. Triple Periodic Minimal Surface (TPMS)-based additively manufactured gyroid structures offer a mean curvature of zero, rendering this structure an ideal porous architecture. Previous studies have demonstrated the ability of these structures to effectively mimic the mechanical cues required for optimal implant construction. The porous nature of gyroid materials enhances bone ingrowth, thereby improving implant stability within the body. This enhancement is attributed to the increased surface area of the gyroid structure, which is approximately 185% higher than that of a dense material of the same form factor. This larger surface area allows for enhanced cellular attachment and nutrient circulation facilitated by the porous channels. This study aims to evaluate the biological performance of a gyroid-based Ti6Al-4V implant material compared to a dense alloy counterpart. Cellular viability was assessed using the lactate dehydrogenase (LDH) assay, which demonstrated that the gyroid surface allowed marginally higher viability than dense material. The integration was studied over 6 weeks using a rabbit tibia model and characterized using X-ray, micro-CT, and histopathological examination. With a metal volume of 8.1%, the gyroid exhibited a bone volume/total volume (BV/TV) ratio of 9.6%, which is 11-fold higher than that of dense metal (0.8%). Histological assessments revealed neovascularization, in-bone growth, and the presence of a Haversian system in the gyroid structure, hinting at superior osteointegration.
植入物构建的仿生方法是植入学领域一个新兴的前沿领域。基于三重周期极小曲面（TPMS）的增材制造类螺旋结构平均曲率为零，使其成为理想的多孔结构。先前的研究表明，这些结构能够有效模拟最佳植入物构建所需的机械信号。类螺旋材料的多孔性质促进了骨向内生长，从而提高了植入物在体内的稳定性。这种增强归因于类螺旋结构表面积的增加，其比相同外形的致密材料大约高185%。更大的表面积使得多孔通道促进了细胞附着和营养物质循环。本研究旨在评估基于类螺旋的Ti6Al-4V植入材料与致密合金对应物相比的生物学性能。使用乳酸脱氢酶（LDH）测定法评估细胞活力，结果表明类螺旋表面的细胞活力略高于致密材料。使用兔胫骨模型在6周内研究整合情况，并通过X射线、微型计算机断层扫描（micro-CT）和组织病理学检查进行表征。在金属体积为8.1%的情况下，类螺旋结构的骨体积/总体积（BV/TV）比为9.6%，是致密金属（0.8%）的11倍。组织学评估显示类螺旋结构中有新血管形成、骨内生长以及哈弗斯系统的存在，这暗示了其卓越的骨整合能力。
